What is the tolerance range of precision screws?
What is the tolerance range of precision screws?
The quality of the combination screw should start with the screw wire of the combination screw manufacturer. The wire of the screw is the first hurdle to determine the quality of the combination screw. Even if the wire is not good, even if the production equipment is advanced and the staff is skilled, it is impossible to produce high-quality combination screws. In the second look at the quality of the combination screw products, from the overall aesthetics of the combination screw. A combined screw is formed, the size of the screw head, the superior appearance of the flat washer, whether the screw thread can pass the stop gauge, etc. These are all things that need to be detected. A good combination screw, its overall standard can meet the national standard requirements, or customer requirements. Finally, the quality of the combination screw product is seen from the color of the plating. Of course, the iron combination screw needs to be plated, but the stainless steel combination screw does not need it. Some of them are passivation at most, in order to increase the salt spray resistance of stainless steel combination screws. In the electroplating color of the combination screw, some of them are not well controlled, which will produce a great color difference. That doesn't look good.
According to the properties of nuts, there are mainly national standard (GB), German standard (DIN), international standard (ISO), Japanese standard (JIS), American standard (ASTM/ANSI) and other standards. Among them, the national standard, German standard, and Japanese standard are represented by M (such as M8, M16), and the American system and the British system are represented by fractions or # (such as 8#, 10#, 1/4, 3/8). Commonly used national standard GB41 Ⅰ type hexagonal nut - C grade GB6170 Ⅰ type hexagonal nut - A, B grade GB6171 I type hexagonal nut - fine thread - A, B grade GB6172 hexagonal thin nut - A, B grade - chamfering GB6173 Hexagonal Thin Nut - Fine Thread - A, B Grade GB6174 Hexagon Thin Nut - B Grade - No Chamfer GB6175 II Hexagonal Nut - A, B Grade GB6176 II Type Hexagonal Nut - Fine Thread - A, B Grade GB6177 Hexagon Method Blue face nut - grade A GB55 hexagonal thick nut GB56 hexagonal super thick nut GB1229 large hexagonal nut (high strength for steel structure)
In recent years, more fasteners have been used in rivet nuts, which have replaced some existing welding methods to a certain extent. Rivet nuts are a way to join some difficult-to-weld equipment and other components. The use of rivet nuts requires rivet nut equipment (manual rivet nut equipment, etc.). Matters needing attention before using manual rivet nut equipment. 1. First, make sure the nozzle screws are properly assembled. According to the size of the rivet nut, select the appropriate equipment and rivet bolt. Every connecting part is not secure. 2. Confirm the deformation length or displacement of the rivet nut, and then leverage the long angle. 3. The scale ring of the rivet nut equipment is used to adjust the rivet stroke, which can be adjusted freely as needed. When adjusting the length of the rivet bolt, open the two handles and adjust the device head sleeve. The rivet bolts are exposed for a length slightly greater than the length of the rivet nut, which will eventually adjust the nut and device sleeve.
The spring washer can prevent loosening and increase the pre-tightening force, while the flat washer does not have this function. It can be used to increase the tightening contact area, prevent the friction between the bolt and the workpiece, and protect the surface of the connector to prevent bolts. The surface of the workpiece is scratched when the nut is tightened. However, for some important connections, such as places that rely mainly on compression to generate frictional force to transmit power, spring pads cannot be used, and the rigidity of the connection is reduced, which is prone to accidents. Spring washers can be omitted. When the strength of the connected parts is low, use flat washers or flange bolts to increase the contact area. When there is vibration, pulse, and the temperature of the medium fluctuates greatly, spring washers must be used.
The above content is uploaded by Yueluo or the Internet. If there is any copyright issue, please contact [email protected].
